President Barack Obama, at the White House today, will hail the 42nd consecutive month of job growth — and a noteworthy monthly gain, in comparison with the past two months. June’s weak gain has been revised downward today to 64,000.

Republican Mitt Romney, campaigning in Las Vegas today, will focus on that jobless rate — over 8 percent heading into an election, and, for now, rising.

Today, in a statement issued by the candidate on his way to Las Vegas, he called the July report “a hammer blow.”

“Today’s increase in the unemployment rate is a hammer blow to struggling middle-class families,” Romney said in the statement issued by his campaign. “We’ve now gone 42 consecutive months with the unemployment rate above eight percent. Middle class Americans deserve better, and I believe America can do better.”)

(Second update:

Alan Krueger, chairman of the White House’s Council of Economic Advisers, issued his own statement today.

The administration’s take-away:

“While there is more work that remains to be done, today’s employment report provides further evidence that the U.S. economy is continuing to recover from the worst downturn since the Great Depression. It is critical that we continue the policies that build an economy that works for the middle class as we dig our way out of the deep hole that was caused by the severe recession that began in December 2007.”)

Today’s monthly unemployment report from the Department of Labor provides Romney a fresh chance to highlight discontent over the economy even as Obama pre- empted him with a swing-state ad campaign attacking the challenger’s tax plan, Bloomberg’s Mike Dorning reports.

The jobs report probably won’t sway many voters, says Dan Schnur, a campaign adviser to Republican presidential candidate John McCain’s first bid for the White House.

“Voters already know what they think about the economy,” says Schnur, director of the Unruh Institute of Politics at the University of Southern California in Los Angeles. “What’s left is for them to decide who can do something to make it better.”